Beitunya , West Bank -LRB- CNN -RRB- -- Fakher Zayed is accustomed to trouble erupting on his doorstep .

For the past several years , Palestinian protesters have often clashed with Israeli security forces in front of his house . The four-story building stands on the edge of the West Bank village of Beitunya , within sight of the Israeli separation barrier and Ofer prison .

At first , the May 15 anniversary of the `` Nakba , '' the exodus of more than 700,000 Palestinians after the 1948 Arab-Israeli war , looked like just another day of Israeli-Palestinian skirmishing .

'' -LRB- The Palestinians -RRB- were throwing stones , and the -LRB- Israeli -RRB- soldiers throw the tear gas . Plastic bullets , '' Zayed said . `` They run away . After three or four minutes , they came back to throw stones again . ''

To protect his home , his family and his carpentry business , Zayed installed more than half a dozen security cameras around his building , which operate 24 hours a day .

Last Thursday , these cameras captured the chilling shooting deaths of two Palestinian teenagers . According to six hours of raw , unedited video distributed by the children 's rights advocacy organization Defense for Children International and reviewed by CNN , the two boys -- ages 17 and 16 -- were shot on the same patch of asphalt on the same day , the second victim 73 minutes after the first .

The families of the boys , as well as Zayed , blame the Israeli military for the killings .

`` This is the first time they 're shooting to kill here , '' Zayed said , speaking to CNN while standing on the exact spot outside his home where the two boys were filmed being shot .

But an Israeli military spokesman say its forces fired no live rounds during hours of clashes on May 15 .

`` During that demonstration that was extremely violent , the Israeli Defense Force used crowd-control methods and riot-dispersal means to prevent and control the overflow of the violence , '' Lt. Col. Peter Lerner told CNN .

`` The preliminary IDF inquiry indicates that no live fire was shot at all on Thursday during the riots in Beitunya , and we have to determine what caused this result , '' Lerner added .

Security camera footage

CNN producer Kareem Khadder was filming the clashes in Beitunya on May 15 .

Several dozen Palestinian youths used the wall of Zayed 's house as cover . Periodically , they jumped out to hurl stones at about a half-dozen Israeli soldiers and border police officers standing on a hilltop perhaps 100 meters away . The Israeli forces responded with volleys of tear gas while periodically firing rubber-coated bullets from their rifles .

At one point , Khadder filmed a Palestinian teenager who appeared to be struck in the leg with one of these semi-lethal rounds . The boy hopped and limped for a few seconds in obvious pain but then turned around and rejoined the clashes .

At 1:45 p.m. May 15 , Zayed 's security camera caught the moment when one of the stone-throwing boys was mortally wounded .

Seventeen-year-old Nadeem Nouwarah was dressed in a sleeveless black t-shirt , wearing a black and white kefiyeh scarf to cover his face and carrying a backpack over both shoulders . As he walked toward the Israeli military positions in front of Zayed 's door , Nouwarah suddenly fell forward , landing briefly on his hands , before rolling over to lie on his back .

Within seconds , a crowd of Palestinians gathered to lift Nouwarah and rush him to a waiting ambulance . According to a medical report , Nouwarah was pronounced dead in a hospital less than two hours later , having suffered a single bullet wound that entered his chest and passed out his back .

Though Khadder did n't know it at the time , he was filming two Israeli security troops firing their rifles at the Palestinian protesters at the same exact moment when Nouwarah was shot . In the video , it is not clear what kind of rounds the Israelis were shooting or whether their gunfire hit Nouwarah . However , Khadder 's camera shows that less than 15 seconds after one of these gunshots , Palestinians were already racing to put the fatally wounded Nouwarah in the ambulance .

Suffering the effects of tear gas , Khadder soon left the protest . He was unaware that Nouwarah 's wounds were fatal .

At 2:58 p.m. , the security cameras filmed a second fatal shooting . Sixteen-year-old Mohammad Odeh Salameh was at the front lines of the protest , wearing a green Hamas flag as a cape as well as a green Hamas headband over his black mask .

As he was walking away from the Israeli positions , he suddenly fell to the ground and struggled briefly to get up . The boy was shot just a few steps from where Nouwarah had been wounded .

Doctors pronounced Salameh dead on arrival at the hospital , with a bullet wound that had pierced his back and exited his chest .

School in mourning

At St. George 's school in Ramallah , relatives and classmates of the first victim , Nouwarah , were in mourning this week . Students wore black t-shirts with photos of the smiling boy . The eleventh-grader was pictured wearing a backward baseball cap .

`` There were 21 students in our grade , '' said his 16-year-old classmate George Yousef . `` Now , we are 20 . ''

Nouwarah 's father , Siam , told CNN he had expressly instructed his eldest son not to attend the Nakba protests .

`` Afterwards , I felt he was not convinced with what I told him , '' said Siam , who works as a hairdresser in Ramallah .

Nouwarah appeared to have gone to the anti-Israel protests directly from school on the afternoon of May 15 . His father showed CNN the bloody backpack his son was wearing when he was shot .

There was a small hole in the bag , in roughly the same location where the bullet would have exited Nouwarah 's body .

Siam Nouwarah then pulled a packet of bloodstained papers out of the bag . They were photocopies of a textbook that included the writings of Anton Chekhov , accompanied by a teenage student 's handwriting , doodles and class notes .

`` We were surprised when we took the school backpack back from the hospital to find this bullet inside , '' said the elder Nouwarah . He then pulled a small used bullet stored in a plastic bag out of the backpack .

The metal slug appeared to be from a 556 NATO round , the standard ammunition used in M-16 rifles carried by Israeli security forces . It was impossible for CNN to confirm the authenticity of the bullet .

Siam Nouwarah said he was saving it for a forensic examination . He accuses Israeli soldiers of killing his son .

`` The entire world should understand and know that my son was wearing a school backpack and leaving school when he was assassinated in cold blood , '' the grieving father said .

Ballistics

On Thursday , Lerner , the Israeli military spokesman , told CNN that a request had been put in with the Palestinian Authority to do a ballistic report on the bullet found in Nouwarah 's backpack .

`` That round that was presented should n't have been in the bag , so it also raises a question , '' he said . Lerner repeated the military 's assertion that Israeli security forces fired only rubber-coated bullets -- which are not designed to penetrate bodies -- in Beitunya on May 15 .

Regarding the CNN video of the Israeli security forces firing rifles at the Palestinian demonstrators at the moment when Nouwarah was shot , Lerner said the weapons being used had an attachment at the end of the barrel for firing rubber-coated projectiles .

Asked whether there could been some malfunction or mistake that would have led to the firing of a lethal round rather than a rubber-coated projectile , Lerner said , `` I 'm not aware of any malfunction at this time . ''

Meanwhile , the U.S. State Department has joined several human rights groups calling for an investigation into the deadly incident .

`` I am deeply concerned about the circumstances surrounding the recent death of two Palestinian minors , '' wrote Christopher Gunness , a spokesman for the United Nations in the West Bank .

According to initial reports , Gunness added , both boys appeared `` unarmed and appeared to pose no direct threat . ''

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May 15 marks the `` Nakba '' exodus of Palestinians after the 1948 Arab-Israeli war

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During protests in the West Bank this year , two Palestinian youths were shot dead

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Israel 's military says the protest was extremely violent but that `` no live fire was shot ''

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But one of the dead teenager 's fathers alleges his son was `` assassinated in cold blood ''